Global ETD Search

11	Ageing assessment of transformer insulation through oil test database analysis Tee, Sheng Ji January 2016 (has links) Transformer ageing is inevitable and it is a challenge for utilities to manage a large fleet of ageing transformers. This means the need for monitoring transformer condition. One of the most widely used methods is oil sampling and testing. Databases of oil test records hence manifest as a great source of information for facilitating transformer ageing assessment and asset management. In this work, databases from three UK utilities including about 4,600 transformers and 65,000 oil test entries were processed, cleaned and analysed. The procedures used could help asset managers in how to approach databases, such as the need for addressing oil contamination, measurement procedure change and oil treatment discontinuities. An early degradation phenomenon was detected in multiple databases/utilities, which was investigated and found to be caused by the adoption of hydrotreatment oil refining technique in the late 1980s. Asset managers may need to monitor more frequently the affected units and restructure long term plans. The work subsequently focused on population analyses which indicated higher voltage transformers (275 kV and 400 kV) are tested more frequently and for more parameters compared with lower voltage units (33 kV and 132 kV). Acidity is the parameter that shows the highest correlation with transformer in-service age. In addition, the influence of the length of oil test records on population ageing trends was studied. It is found that it is possible to have a representative population ageing trend even with a short period (e.g. two years) of oil test results if the transformer age profile is representative of the whole transformer population. Leading from population analyses, seasonal influence on moisture was investigated which implies the importance of incorporating oil sampling temperature for better interpretation of moisture as well as indirectly breakdown voltage records. A condition mismatch between dielectric dissipation factor and resistivity was also discovered which could mean the need for revising the current IEC 60422 oil maintenance guide. Finally, insulation condition ranking was performed through principal component analysis (PCA) and analytic hierarchy process (AHP). These two techniques were demonstrated to be not just capable alternatives to traditional empirical formula but also allow fast, objective interpretation in PCA case, as well as flexible and comprehensive (objective and subjective incorporations) analysis in AHP case.
12	Analýza a návrh změn informačního systému firmy / Company's Information System Analysis and Modifications Concept Zahradník, Martin January 2009 (has links) This thesis deals with the analysis and design changes to a specific company information system under real conditions, and is therefore more practically oriented. The information system is studied both from the perspective of the end user, which is the focus, and in terms of operation and implementation of program solutions. The information system is studied as a whole in a broader context, not only in terms of applications (software), but also in terms of the flow of information, storage and organization of data, users, security, hardware, etc. It should serve to the company as a guide for the elimination of inefficient and / or risk areas, thereby helping to improve work productivity and employee satisfaction.
13	Posouzení informačního systému firmy a návrh změn / Assessment of the Company's Information System and a Proposal for Amendments Mertel, Ján January 2016 (has links) This diploma thesis aims to offer a solution for selected company in the area of information systems. As a basis it uses analysis according to known models, which are being applied to the situation in selected company. Subsequently it aims to address the actual proposal, in which output the author tries to find an optimal solution, that could be used in the company.
14	Tvorba databázové aplikace a řešení pro Business Intelligence / Creation of Database Application and Solutions for Business Intelligence Městka, Milan January 2012 (has links) Theme of this master’s thesis is design of software support for business intelligence. Design is realized in cooperation with corporation ZZN Pelhřimov a.s. Introduction is focused on theoretical description of business intelligence and datamining and also on development environment in which is project designed. Corporation is characterised also in introduction. Main part contains data collecting and definition of individual modules. In conclusion of this thesis will be several types of analysis from collected data and then according to these analysis, we can draw measures to improve current state of corporation.
15	Characteristics Associated with Neonatal Carnitine Levels: A Systematic Review & Clinical Database Analysis Sutherland, Sarah C. 28 January 2013 (has links) Newborn screening programs measure analyte levels in neonatal blood spots to identify individuals at high risk of disease. Carnitine and acylcarnitine levels are primary markers used in the detection of fatty acid oxidation disorders. These analytes may be influenced by certain pre/perinatal or newborn screening related factors. The primary objective of this study was to explore the association between these characteristics and levels of blood carnitines and acylcarnitines in the newborn population. The study was composed of two parts: a systematic review and a clinical database analysis of existing newborn screening data. The systematic review results suggested considerable variability across studies in the presence and directionality of associations between analyte levels and birth weight, gestational age, age at time of blood spot collection, type of sample, and storage time. Sex was not significantly associated with carnitine or acylcarnitine levels in neonatal blood. We identified a need to more fully investigate a potential interaction between gestational age and birth weight in regard to analyte levels. The secondary data analyses indicated a statistically significant relationship between analyte levels and all perinatal / infant and newborn screening related factors of interest, but effect sizes were generally small. The interaction between gestational age and birth weight was significant in all models; when further explored through graphical analysis with conditional means, extremely premature neonates stood out as having distinct analyte patterns in relation to birth weight. Variation in the ratio of total acylcarnitine to free carnitine was better accounted for by the perinatal and newborn factors than was variation in any individual carnitine or acylcarnitine, indicating that proportions of carnitine and acylcarnitines may be more important in understanding an individual’s metabolic functioning than individual analyte levels. A low proportion of variation was explained in all multivariate models, supporting the use of universal algorithms in newborn screening and suggesting the need for further large scale empirical research targeted at previously unaccounted for perinatal factors such as birth stress. newborn screening neonatal screening carnitine acylcarnitine mass screening inborn errors of metabolism lipid metabolism fatty acid oxidation fatty acid oxidation disorders free carnitine octanoylcarnitine C8 short chain acylcarnitine medium chain acylcarnitine long chain acylcarnitine birth weight gestational age sex age at collection age of collection blood spot heel prick socioeconomic status feeding breast milk formula transit time transfusion false positive Newborn Screening Ontario Ontario Newborn Screening Program database analysis systematic review
16	Characteristics Associated with Neonatal Carnitine Levels: A Systematic Review & Clinical Database Analysis Sutherland, Sarah C. 28 January 2013 (has links) Newborn screening programs measure analyte levels in neonatal blood spots to identify individuals at high risk of disease. Carnitine and acylcarnitine levels are primary markers used in the detection of fatty acid oxidation disorders. These analytes may be influenced by certain pre/perinatal or newborn screening related factors. The primary objective of this study was to explore the association between these characteristics and levels of blood carnitines and acylcarnitines in the newborn population. The study was composed of two parts: a systematic review and a clinical database analysis of existing newborn screening data. The systematic review results suggested considerable variability across studies in the presence and directionality of associations between analyte levels and birth weight, gestational age, age at time of blood spot collection, type of sample, and storage time. Sex was not significantly associated with carnitine or acylcarnitine levels in neonatal blood. We identified a need to more fully investigate a potential interaction between gestational age and birth weight in regard to analyte levels. The secondary data analyses indicated a statistically significant relationship between analyte levels and all perinatal / infant and newborn screening related factors of interest, but effect sizes were generally small. The interaction between gestational age and birth weight was significant in all models; when further explored through graphical analysis with conditional means, extremely premature neonates stood out as having distinct analyte patterns in relation to birth weight. Variation in the ratio of total acylcarnitine to free carnitine was better accounted for by the perinatal and newborn factors than was variation in any individual carnitine or acylcarnitine, indicating that proportions of carnitine and acylcarnitines may be more important in understanding an individual’s metabolic functioning than individual analyte levels. A low proportion of variation was explained in all multivariate models, supporting the use of universal algorithms in newborn screening and suggesting the need for further large scale empirical research targeted at previously unaccounted for perinatal factors such as birth stress. newborn screening neonatal screening carnitine acylcarnitine mass screening inborn errors of metabolism lipid metabolism fatty acid oxidation fatty acid oxidation disorders free carnitine octanoylcarnitine C8 short chain acylcarnitine medium chain acylcarnitine long chain acylcarnitine birth weight gestational age sex age at collection age of collection blood spot heel prick socioeconomic status feeding breast milk formula transit time transfusion false positive Newborn Screening Ontario Ontario Newborn Screening Program database analysis systematic review
17	Characteristics Associated with Neonatal Carnitine Levels: A Systematic Review & Clinical Database Analysis Sutherland, Sarah C. January 2013 (has links) Newborn screening programs measure analyte levels in neonatal blood spots to identify individuals at high risk of disease. Carnitine and acylcarnitine levels are primary markers used in the detection of fatty acid oxidation disorders. These analytes may be influenced by certain pre/perinatal or newborn screening related factors. The primary objective of this study was to explore the association between these characteristics and levels of blood carnitines and acylcarnitines in the newborn population. The study was composed of two parts: a systematic review and a clinical database analysis of existing newborn screening data. The systematic review results suggested considerable variability across studies in the presence and directionality of associations between analyte levels and birth weight, gestational age, age at time of blood spot collection, type of sample, and storage time. Sex was not significantly associated with carnitine or acylcarnitine levels in neonatal blood. We identified a need to more fully investigate a potential interaction between gestational age and birth weight in regard to analyte levels. The secondary data analyses indicated a statistically significant relationship between analyte levels and all perinatal / infant and newborn screening related factors of interest, but effect sizes were generally small. The interaction between gestational age and birth weight was significant in all models; when further explored through graphical analysis with conditional means, extremely premature neonates stood out as having distinct analyte patterns in relation to birth weight. Variation in the ratio of total acylcarnitine to free carnitine was better accounted for by the perinatal and newborn factors than was variation in any individual carnitine or acylcarnitine, indicating that proportions of carnitine and acylcarnitines may be more important in understanding an individual’s metabolic functioning than individual analyte levels. A low proportion of variation was explained in all multivariate models, supporting the use of universal algorithms in newborn screening and suggesting the need for further large scale empirical research targeted at previously unaccounted for perinatal factors such as birth stress. newborn screening neonatal screening carnitine acylcarnitine mass screening inborn errors of metabolism lipid metabolism fatty acid oxidation fatty acid oxidation disorders free carnitine octanoylcarnitine C8 short chain acylcarnitine medium chain acylcarnitine long chain acylcarnitine birth weight gestational age sex age at collection age of collection blood spot heel prick socioeconomic status feeding breast milk formula transit time transfusion false positive Newborn Screening Ontario Ontario Newborn Screening Program database analysis systematic review

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